Polyamide reverse osmosis (RO) membrane with thin film composite structure was commercialized for seawater desalination process. Recently, it has been reported that some RO processes for high pressure and recovery leads to reducing in energy cost and pretreatment scale compared with earlier process. The development of energy recovery, pumping device and RO elements with high pressure and rejection made high pressure and recovery process possible. In this study, permeation properties of commercialized seawater RO membrane were investigated under the condition of high pressure and recovery. In the RO sheet membrane test 3.5% NaCl of synthetic seawater was used. The synthetic seawater contained only sodium chloride. In the RO module test, natural seawater was used at Happo Bay, Masan city. As the results, RO membrane with high durability of pressure was better than that with high rejection of seawater for high pressure and recovery process. Seawater rejection of high concentrate tends to be improved by high pressure operation.